Device for opening and closing a closure cap

ABSTRACT

The invention concerns a device for opening and closing a closure cap (16) fitted over a cleaning aperture (10) in the floor of the discharge container (12) of a pump (14) for thick-bodies fluids. The cap (16) is linked to a hydraulic drive unit (20) and can be swung out hydraulically, when a control valve (48) is actuated, into the open position in which the discharge outlet is left open. The cap (16) is swung back into the closed position by means of a hand-operated lever (23), the hydraulic drive unit (20) being returned at the same time to its initial position.

FIELD OF THE INVENTION

The invention relates to a device for opening and closing a closure caparranged on a bottom-side cleaning opening of a container, inparticular, a material-feeding container for thick-matter pumps.

BACKGROUND OF THE INVENTION

In a conventional arrangement of this type, the closure cap is arrangedon a container-fixed hinge joint, can be opened for emptying andcleaning of the feeding container of a concrete pump, and closedmanually by swivelling. Increased frictional resistances occur, inparticular during the opening operation, due to material adhering to theclosure cap. These frictional resistances make the manual operation ofthe closure cap more difficult.

In order to make the operation easier, it would be possible to provide ahydraulic device for opening and closing of the closure cap. However,one must thereby consider that in such devices injury to an operatormust be prevented through suitable safety measures. This, as a rule,requires additional equipment and related increased expense.

SUMMARY OF THE INVENTION

Starting out from this, the basic purpose of the invention is to providea simple arrangement of the above-identified type, with which a closurecap on a container, as for example a material-feeding container of athick-matter pump, can be opened and closed by one operator with littleeffort and without any danger of injury.

The invention is based on the thought that during the hydraulic openingof the closure cap, a danger of injury is essentially eliminated andthat vice versa during closing of the closure cap, when the container isempty and has been cleaned, the manual closing does not require anyparticular strength. Accordingly, the invention suggests a hydraulicdrive unit, which can be moved between an output and an end position andis coupled to the closure cap, for adjusting the closure cap between aclosing position sealing off the cleaning opening and an outlet positionat least partially releasing the cleaning opening, whereby the closurecap can be adjusted into its outlet position by operating a hydrauliccorrecting element controlling the pressure oil supply to the hydraulicdrive unit and can be manually returned into its closing position bymeans of a mechanical control member with a simultaneous return of thehydraulic drive unit into its initial position.

The hydraulic drive unit has according to a preferred embodiment of theinvention a drive piston, which can be moved in a one-way operatinghydraulic cylinder, which can be loaded on the bottom side withpressurized oil and is connected on the rod side to an oil tank or tothe atmosphere.

The feeding movement of the drive piston can be converted in acontainer-fixed hydraulic cylinder through a linkage connected to thepiston rod into a pivoting movement of the closure cap. The drive pistoncan, as an alternative, be coupled through a rocking lever hinged on thepiston rod to the closure cap, whereby the hydraulic cylinder in thiscase is pivotally arranged about an axis parallel to the axis of thecleaning opening on the container.

For the manual closing of the closure cap, the mechanical control membercan be constructed as a handle or hand lever connected rigidly to thepiston rod or to the closure lid.

The hydraulic supply to the hydraulic cylinder is advantageouslycontrolled by a control valve designed as a 3/2-directional valve,whereby the bottom side of the hydraulic cylinder is connected, in apreferably manually operated switching position of the directionalvalve, to the pressure-oil supply and in the spring-centered restposition of the directional valve to the oil tank. Thus an incorrecthandling of the hydraulic drive unit is essentially eliminated. At thesame time, it is assured that the pressurized oil can, without anyfurther measures, be removed from the bottom area of the drivingcylinder upon operation of the mechanical control member and thus thehydraulic piston can be returned into its initial position.

For the measured discharge of the goods existing in the container, it ispossible to control the opening speed of the closure cap with a flowvalve preferably designed as a regulatable throttle valve to influencethe pressurized oil supply to the hydraulic drive unit.

To limit the closing movement and the liquid-tight sealing of thecleaning opening, the closure lid is advantageously pressed through anabutting slope of a stop piece arranged on the container bottom in itsclosing position against a sealing ring.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be discussed in greater detail hereinafter inconnection with the exemplary embodiments schematically illustrated inthe drawings, in which:

FIGS. 1 and 2 are partially diagrammatic views of an arrangement forclosing a cleaning opening of a container with the closure cap beingopen and closed.

FIG. 3 is a bottom view of a further modification of a closurearrangement in a closed (full lines) and an open (dashed lines)position.

DETAILED DESCRIPTION

The closure arrangements illustrated in the drawings consist essentiallyof a closure cap 16 arranged on a bottom-side cleaning opening 10 of acontainer 12 of a thick-matter pump 14. The cap is coupled to ahydraulic drive unit 20, whereby the closure cap can be hydraulicallyopened after the release of a hydraulic correcting element 22 and canagain be closed liquid-tight by operating a mechanical control memberdesigned as a hand lever 23.

The hydraulic drive unit 20 has a drive piston 26 movable in a one-wayacting hydraulic cylinder 24, which piston in the exemplary embodimentaccording to FIGS. 1 and 2 is coupled with the closure cap 16 throughits piston rod 28 and a linkage 18 consisting of two coupling members32, 36 connected through hinge joints 30, 34 to the piston rod 28 and toone another. The cap in turn is arranged pivotally about an axis 58,which is parallel to the axis of the cleaning opening 10, on the outsidebottom of the container.

The cleaning opening 10 is, during the operation of the thick-matterpump 14, closed off liquid-tight by the closure cap 16, which is in itsclosing position. To convey the material fed into the container 12, thethick-matter pump 14 has two conveyor cylinders 38, 40, the front-sideopenings of which end in the container 12 and are during the pressurestroke alternately connected through a swivel pipe 42 to a feed pipeline44.

The closure cap 16 is hydraulically opened in order to empty out theresidual material in the container 12 (FIG. 1). The hydraulic correctingelement 22, which is arranged between the bottom connection of thehydraulic cylinder 24 and the pressure side of a pump 46, and whichconsists of a 3/2(three port, two position)-directional valve 48 and aregulatable throttle valve 50 connected in front of the directionalvalve 48, is for this purpose operated. The directional valve 48, whichis manually operated by means of a release member 52, connects in itsswitching position a the bottom end of the hydraulic cylinder 24 to thepressurized oil supply, which causes the piston 26 to be moved therebyswivelling the closure cap 16 into its opened position exposing thecleaning opening 10. The rod side of the hydraulic cylinder 24 isthereby either, as illustrated, connected to an oil tank 51, or,however, is directly relieved to the atmosphere. In order to measure theoutflow of the goods out of the cleaning opening 10, it is possible tocontrol its opening speed with a regulated throttling of thepressure-oil supply through the throttle valve 50.

When letting go of the release member 52, the directional valve 48returns into its spring-centered rest position b, in which it connectsthe bottom end of the hydraulic cylinder 24 to the oil tank 51 (FIG. 2).The closure cap 16 can in this position after the container 12 has beenemptied be swung back into its closing position by means of the handlever 23 rigidly arranged on the piston rod 28. The hand lever 23 is forthis purpose pressed in direction of the arrow 54 with a simultaneousreturn of the piston 26 into its initial position, whereby thepressurized oil flows from the bottom side back to the rod side of thehydraulic cylinder 24 or into the tank 51.

FIG. 3 shows a modified exemplary embodiment of a closure arrangement,in which the same parts have been identified with the same referencenumerals. The hydraulic cylinder 24 is, in this embodiment, arrangedpivotally about a container-fixed axis 56 on the bottom of the containerand the piston rod is connected to the closure lid 16 through a rockinglever 64, which is rotatable about the container-fixed axis 58, wherebythe pivot axes 56, 58 and the axis of the hinge joint 30 are arrangedparallel to the axis of the cleaning opening 10. The closure lid 16 canbe swung by means of the hydraulical drive unit 20 in the alreadydescribed manner hydraulically into its outlet position and can be swungback into its closing position against the stop pieces 60 by means ofthe hand lever 23, which is rigidly connected to the closure lid 16. Theclosure lid 16 grips thereby under an abutting slope 61 constructed onthe stop pieces 60, and is thus in its closing position pressed againsta sealing ring, which seals liquid-tight the cleaning opening 10.

Closure devices of the invention can, aside from the above-mentioneduses, also be used on other feed and storage containers and on premixingtroughs.

In summary the following can be stated: The invention relates to adevice for opening and closing of a closure cap 16 arranged on abottom-side cleaning opening 10 of a material-feeding container 12 of athick-matter pump 14. The closure cap 16 coupled with the hydraulicdrive unit 20 can be swung out hydraulically into its outlet positionreleasing the cleaning opening 10 by operating a control valve 48. Theswinging back of the closure cap 16 into its closing position is donemanually by means of a mechanical control member 23 with a simultaneousreturn of the hydraulic drive unit 20 into its initial position.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. A device for opening andclosing a closure cap arranged on a bottom-side cleaning opening of acontainer, comprising a pump generating a fluid pressure supply, ahydraulic drive unit, movable between initial and end positions andbeing coupled with the closure cap for only adjusting the closure capfrom a closed position sealing off the cleaning opening when said driveunit is at said initial position to an open position at least partiallyexposing the cleaning opening when said drive unit is at said endposition, a hydraulic correcting element fluidly connected to thehydraulic drive unit for controlling the pressure supply to thehydraulic drive unit to effect a hydraulic powered movement of theclosure cap into the open position and an unpowered movement of theclosure cap to the closed position, and a control means for manuallysimultaneously moving the closure cap to the closed position and thehydraulic drive unit to the initial position.
 2. The device according toclaim 1, wherein the hydraulic drive unit has a drive piston, and aone-way operating hydraulic cylinder movably receiving the drive pistontherein, the drive piston defining a bottom side and rod side in thehydraulic cylinder, the hydraulic cylinder being loaded with pressurizedfluid on the bottom side and is connected on the rod side to one of afluid tank and the atmosphere.
 3. The device according to claim 2,wherein the drive piston includes a rod, and a linkage connects theclosure cap to the rod.
 4. The device according to claim 3, wherein thecontrol means is one of a handle and hand lever rigidly connected to oneof the rod and the closure cap.
 5. The device according to claim 2,wherein the drive piston includes a rod, and wherein a rocking lever iscoupled to the closure cap while simultaneously being hinged to the rod.6. The device according to claim 5, wherein the hydraulic cylinder ispivotal about a container-fixed axis, the container-fixed axis beingparallel to an axis of the cleaning opening.
 7. The device according toclaim 1, wherein the closure cap is pivotally fixed to the container andis pivotal about an axis parallel to the axis of the cleaning opening.8. The device according to claim 2, wherein the hydraulic correctingelement is a control valve designed as a 3/2 directional valve.
 9. Thedevice according to claim 8, wherein the bottom side of the hydrauliccylinder is connected to the control valve, and the control valve in amanually operated switching condition thereof connecting the bottom sideto the pressure supply and in a resting condition thereof connecting thebottom side to a fluid tank.
 10. The device according to claim 9,wherein a spring is provided for returning the control valve to theresting condition whereat the bottom side of the hydraulic cylinder isconnected through the control valve to the fluid tank.
 11. The deviceaccording to claim 1, wherein the hydraulic correcting element has aflow valve for regulating the pressure supply from the pump to thehydraulic drive unit.
 12. The device according to claim 1, wherein astop niece is arranged on the bottom of the container adjacent thecleaning opening, the stop piece having a slope thereon, and wherein asealing ring surrounds the cleaning opening, the closure cap beingpressed in the closed position against the sealing ring through theslope of the stop piece.
 13. A device for opening and closing a cleaningopening of a material-feed container, comprising a closure lid adaptedto be in first and second positions respectively closing and opening thecleaning opening, a pump generating a fluid pressure supply, a one-wayacting drive cylinder being connected to the closure lid and selectivelyconnected to the pump for receiving the fluid pressure supply, ahydraulic element being fluidly connected between the one-way actingdrive cylinder and the pump for controlling the flow of the fluidpressure supply to the drive cylinder, the one-way acting drive cylindereffecting movement of the closure lid only to the second position whenreceiving the fluid pressure supply, and means for manually moving theclosure lid into the first position.
 14. The device according to claim13, wherein the means for manually moving the closure lid also manuallymoves the drive cylinder to a position corresponding to a closedposition of the closure lid.